Active clinical trials for "Venous Thrombosis"

Introduction Undiagnosed deep vein thrombosis (DVT) can lead to significant morbidity and mortality, including death from DVT-associated massive pulmonary embolism (PE). While several validated clinical prediction rules, blood test and imaging modalities exist to investigate a potential DVT, there is currently a lack of rapid, accessible and reliable methods to exclude the possibility of DVT without resorting to formal venous duplex scanning. Currently, the use in the ED of a validated clinical prediction rule combined with high-sensitivity D-dimer test has a poor predictive value, as 75-90% of patients suspected of DVT have a negative formal venous duplex scan. Compression bedside ultrasound has however recently been shown to be a safe, rapid and accurate method for the diagnosis of proximal DVT in the emergency department with a high sensitivity and specificity (combined sensitivity and specificity of 96.1% and 96.8%, respectively1). Research Question In the present study, the investigators will primarily assess whether two-site compression POCUS combined with a negative age-adjusted D-dimer test can accurately rule out DVT in ED patients regardless of the Wells criteria. Methods This is a single-center, prospective, observational study carried out over one year in the Emergency Department of the Jewish General Hospital in Montreal, Quebec. The investigators aim to enroll a convenience sample of 475 patients aged 18 years and older presenting to the ED with symptoms suggestive of a DVT. All enrolled patients will receive the standard of care required for a lower leg DVT presentation. After calculating Patients DVT risk using modified wells criteria, all patients will undergo POCUS for DVT followed by a D-dimer test. Based on their results, patients will either undergo formal duplex scanning, or will be discharged without further testing and receive a three-month phone follow-up. A true negative lower leg DVT will be defined as follows: Negative follow-up phone questionnaire for patients who were sent home with no formal duplex venous scanning. Negative formal duplex venous scanning for patients who were deemed likely to have lower leg DVT using the Wells score, with a negative D-dimer and POCUS Age-adjusted DVT was added to account for below knee DVT and avoid the need for patients to return for fellow up duplex study in 1 week. To estimate our technique's sensitivity with a 4% margin of error with 95% confidence intervals, 92 confirmed DVT patients are needed. The investigators expect to recruit a total 475 patients within one-year period at the JGH (95 DVT-positive patients and 380 DVT-negative patients). Impact The use of compression bedside ultrasound with a negative age-adjusted D-dimer test to rule out DVT in the ED may accelerate the decision regarding patient disposition and significantly decrease the length of patient stay in the ED. In addition, it may help avoid unnecessary medical interventions and diagnostic tests, thus representing potential quality of care and cost-saving improvements as well.

Deep Vein Thrombosis (DVT) is one of the most important complications after Peripherally Inserted Central Catheter (PICC) insertion. This study goals are to understand when and why DVT develops.

After reports from observational studies suggesting an association between acutely ill medical patients and venous thromboembolism (VTE), interventional trials with anticoagulants drugs have demonstrated a significant reduction of VTE during and immediately after hospitalisation. Although several guidelines suggest the clinical relevance of reducing this outcome, there is a low tendency to use anticoagulants in patients hospitalised for acute medical illness. This observational multicentre study wants to evaluate the incidence of venous thrombo-embolism in acutely ill patients hospitalized in internal medicine wards.

Venous thromboembolism (VTE) including deep vein thrombosis (DVT) and pulmonary embolism (PE) affects about 1,200,000 individuals each year in Europe. About 50% of VTE are unprovoked and 20% of these patients will face a recurrent event after the usual three to six-month course of anticoagulant treatment. To date, most patients are given prolonged anticoagulant treatment. However, anticoagulant treatment are associated with a major risk of bleeding (3%/year). Thus an accurate identification of patients with unprovoked VTE with a low risk of recurrence is needed to avoid unnecessary anticoagulant treatment with a risk of bleeding. Over the past few years, microparticles (MPs) which are small vesicles originating from the budding of cellular membranes have emerged as important biological entities regulating hemostasis. MPs expose at their surface procoagulant molecules such as phosphatidylserin and tissue factor (TF). All data obtained in mouse models support a role of MPs in venous thrombosis mediated by the TF activation. Moreover, results from clinical studies showed that TF-MPs was associated with the risk of venous thrombosis. However, the predictive value of TF-MPs in the recurrence of VTE is unknown. Besides, no study has taken into account the recent progresses in the understanding of the role of MPs in haemostasis. Indeed, MPs vectorize molecules which are not only procoagulant but also profibrinolytic. The net result depends on a balance between both activities (the coagulo-lytic balance). This balance is can be measured by two complimentary assays on MPs. We hypothesized that the coagu-lytic balance of MPs is associated with an increased risk of VTE recurrence after stopping the anticoagulant treatment.

Whether the side of implantable CVCs was associated with the complication rates remains unclear. The investigators plan this study to explore this issue by randomizing patients to receive CVC implantation at the left subclavian or righ subclavian vein.

Pregnant women with a prior history of venous thromboembolism (VTE) are at increased risk of recurrent VTE. Current guidelines assessing the role of prophylaxis in pregnant women with prior VTE are based primarily on expert opinion and the optimal clinical management strategy remains unclear. This multicentre, prospective cohort study aims to test the following hypotheses: Antepartum prophylaxis with fixed-dose low molecular-weight heparin (LMWH) is safe, convenient and associated with an acceptably low risk of recurrent VTE in women with a single prior episode of VTE that was either unprovoked or associated with a minor transient risk factor. (Moderate risk cohort) Withholding antepartum prophylaxis is safe (recurrence risk <1%) in pregnant women with a single prior episode of VTE provoked by a major transient risk factor. (Low risk cohort) All study patients will receive 6 weeks of postpartum prophylaxis.

The purpose of this study is to assess validity of extended duplex ultrasound examination for diagnosis of proximal deep vein thrombosis performed by general intensive care unit nurses in the critically ill patients.

Observational. Retrospective cohort.

FEVRIER study is an observatory of hospitalizations in cardiology units in sub-Saharan Africa.

The patients admitted in hospital who had midline catheter inserted in upper limb are followed-up for the presence of complications related to catheter introductions. The symptoms and signs of upper limb thrombosis are recorded. The diagnosis is confirmed by sonography examination. In the selected group of asymptomatic patients sonography examination is done 8 to 10 days after cathether insertion in order to detect the incidence of the asymptomatic thrombosis